A series of geotechnical surveys and in-situ tests were carried out to evaluate the stability of the natural caves and the man-made underground mine openings for an abandoned gold mine. After the closure of the mine, both the natural caves and the man-made underground openings are being served as tourist route. Therefore, it has become essential to analyze the stability of the entire subsurface caves for ensuring safety of visitors. Multistage convergent photography technique was applied in order to determine joint characteristics in one of the large natural caves. Detailed investigations are performed to evaluate RMR, GSI and Q values for stability analysis of caves and for designing required support systems of the unstable openings. Numerical analysis has been carried out to examine the risk of rock fall. Based upon the stability analysis, support patterns for the underground openings are recommended. A special structural design was also introduced in order to protect the visitors from unexpected collapse of the large natural caves and the mined caverns.
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